I recently moved to the West Coast for a new job. I periodically ask if someone is going to take choice A or choice B. Commonly they answer "yes" or "no." I always asked them to re-state by writing "choice " or "choice ". A few said I knew exactly what they meant, I just like to be difficult. I tried to sincerely ask a few coworkers what "yes" and "no" meant in this context and they just frowned and sighed. Where I'm from no one answers "yes". Is this grammatically correct and if so what does it mean?
Bob: Jim, are you taking next week off or the following week?
Jim: Yes
Which week is Jim taking off?
I know this.
Bob: Jim are you taking either next week or the following week off?
Jim: Yes
Means Jim is may be taking next week off or he may be taking the following week off. He's not indicating which week, he's just indicating that it will be one of those 2 weeks, not neither of those 2 weeks.